How much less effective is my birth control once I take antibiotics?

My birth control is tri sprintec, ive taken it everyday at the same time. Monday i had sex without a condom. Today is Wednesday and im sick so I'm taking amoxicillin starting today. Will i get pregnant even though i had sex 2 days ago. How much less effective is my birth control?

Responses (1)

The sex you had was protected and you are safe. Any sex while you take the antibiotic and for a week after you stop you need to use another form of birth control. There is no way to measure how much less it makes your birth control.